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A322444 Primes that are not base-8 deletable primes (written in base 10). 1

%I

%S 71,73,79,97,103,113,127,149,173,193,227,241,257,263,271,281,283,307,

%T 311,313,409,419,433,439,449,457,463,487,503,521,569,577,587,593,599,

%U 607,617,631,641,647,653,661,673,701,727,733,739,743,757,769,823,827,839,881,887,907,911,919,929

%N Primes that are not base-8 deletable primes (written in base 10).

%C A prime p is a base-b deletable prime if when written in base b it has the property that removing some digit leaves either the empty string or another deletable prime.

%C Deleting a digit cannot leave any leading zeros in the new string. For example, deleting the 2 in 2003 to obtain 003 is not allowed.

%C Complement of all primes and A322443 .

%H Robert Price, <a href="/A322444/b322444.txt">Table of n, a(n) for n = 1..660</a>

%t b = 8; d = {};

%t p = Select[Range[2, 10000], PrimeQ[#] &];

%t For[i = 1, i <= Length[p], i++,

%t c = IntegerDigits[p[[i]], b];

%t If[Length[c] == 1, AppendTo[d, p[[i]]]; Continue[]];

%t For[j = 1, j <= Length[c], j++,

%t t = Delete[c, j];

%t If[t[[1]] == 0, Continue[]];

%t If[MemberQ[d, FromDigits[t, b]], AppendTo[d, p[[i]]]; Break[]]]]; Complement[Table[Prime[n], {n, PrimePi[Last[d]]}], d] (* _Robert Price_, Dec 08 2018 *)

%Y Cf. A080608, A080603, A096235-A096246, A321657.

%K nonn,base,easy

%O 1,1

%A _Robert Price_, Dec 08 2018

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Last modified May 16 14:39 EDT 2021. Contains 343949 sequences. (Running on oeis4.)